1. Technical Field
The present invention relates to conveyor belt cleaning apparatus for attachment near the discharge end of a conveyor belt assembly for cleaning away debris adhering to the conveyor belt.
2. Description of Related Art
A primary function of conveyor belt cleaners is to remove debris that remains on the conveyor belt after the belt has rounded the drum at the discharge end of the conveyor (i.e., “carry-back debris” or simply “carry-back”) so as to cause the conveyor belt apparatus malfunction or clog. The main drawback of previously known conveyor belt cleaners is that either they do not remove sufficient “carry-back” from the underside of the conveyor belt or that the debris removed tends to accumulate on the body and/or blade of the cleaner itself and thereby reduces its effectiveness. In either case, the conveyor operation must be stopped repeatedly so that maintenance operations can be performed to allow service personnel to clean the conveyor belt or the conveyor belt cleaner, as the case may be.
U.S. Pat. No. 5,014,844 describes a conveyer belt cleaner that is made of body and a plurality of cleaner elements attached side by side to the body. Each cleaner element has a blade, a blade holder attached to the body and a torsion spring located between the blade and the blade holder. The blade consists of an upper part that is pressed against the underside of the conveyer belt and a lower part that is attached to the torsion spring. The described conveyor belt cleaner consists of a single row of cleaning blades.
U.S. Pat. No. 5,222,589 describes a conveyer belt cleaner that consists of a single blade. The blade is curved and positioned at the underside of the discharge end of the conveyer belt. The curved shape of the blade not only scrapes the conveyer belt but also protects against the blade damaging the belt.
U.S. Pat. No. 5,031,710 describes a conveyer belt cleaner that is attached to the belt and employs the use of a scraper and several nozzles that dispense liquid. A beam that acts as a liquid reservoir carries liquid from a liquid source to the nozzles. Theses nozzles are placed transversely below the conveyer belt along with the scraper. The liquid is sprayed to remove debris from the conveyer belt before the scraper removes carry-back debris.
U.S. Pat. No. 4,269,301 describes a conveyer belt cleaner that consists of three scraper blades positioned against a conveyor belt at the discharge end drum. Each blade is secured to an operating lever which may be rotated by an air cylinder and thereby flex the scraper blade against the conveyor belt. The pressures in the three separate air cylinders are adjusted so that the first scraper blade receives the greatest flexing force, the second scraper blade a lesser flexing force, and the third scraper blade the least flexing force. The differential flexing forces is accomplished by supplying the air cylinders through progressively differently set pressure reducing valves connected to a common compressed air main.
Thus, there exists a need for a simple, conveyer belt cleaner without moving parts or power supply that effectively removes carry-back debris without itself requiring frequent maintenance to remove accumulated debris. The present invention substantially fulfills this need.